1# SPDX-License-Identifier: GPL-2.0-only 2# 3# For a description of the syntax of this configuration file, 4# see Documentation/kbuild/kconfig-language.rst. 5# 6 7config 64BIT 8 bool 9 10config 32BIT 11 bool 12 13config RISCV 14 def_bool y 15 select ACPI_GENERIC_GSI if ACPI 16 select ACPI_MCFG if (ACPI && PCI) 17 select ACPI_PPTT if ACPI 18 select ACPI_REDUCED_HARDWARE_ONLY if ACPI 19 select ACPI_SPCR_TABLE if ACPI 20 select ARCH_DMA_DEFAULT_COHERENT 21 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION 22 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM_VMEMMAP 23 select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG 24 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 25 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE 26 select ARCH_HAS_BINFMT_FLAT 27 select ARCH_HAS_CURRENT_STACK_POINTER 28 select ARCH_HAS_DEBUG_VIRTUAL if MMU 29 select ARCH_HAS_DEBUG_VM_PGTABLE 30 select ARCH_HAS_DEBUG_WX 31 select ARCH_HAS_FAST_MULTIPLIER 32 select ARCH_HAS_FORTIFY_SOURCE 33 select ARCH_HAS_GCOV_PROFILE_ALL 34 select ARCH_HAS_GIGANTIC_PAGE 35 select ARCH_HAS_KCOV 36 select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU 37 select ARCH_HAS_MEMBARRIER_CALLBACKS 38 select ARCH_HAS_MEMBARRIER_SYNC_CORE 39 select ARCH_HAS_MMIOWB 40 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 41 select ARCH_HAS_PMEM_API 42 select ARCH_HAS_PREPARE_SYNC_CORE_CMD 43 select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU 44 select ARCH_HAS_PTE_SPECIAL 45 select ARCH_HAS_SET_DIRECT_MAP if MMU 46 select ARCH_HAS_SET_MEMORY if MMU 47 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 48 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL 49 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 50 select ARCH_HAS_SYSCALL_WRAPPER 51 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 52 select ARCH_HAS_UBSAN 53 select ARCH_HAS_VDSO_DATA 54 select ARCH_KEEP_MEMBLOCK if ACPI 55 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE if 64BIT && MMU 56 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 57 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 58 select ARCH_STACKWALK 59 select ARCH_SUPPORTS_ATOMIC_RMW 60 select ARCH_SUPPORTS_CFI_CLANG 61 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU 62 select ARCH_SUPPORTS_HUGETLBFS if MMU 63 # LLD >= 14: https://github.com/llvm/llvm-project/issues/50505 64 select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000 65 select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000 66 select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU 67 select ARCH_SUPPORTS_PER_VMA_LOCK if MMU 68 select ARCH_SUPPORTS_RT 69 select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK 70 select ARCH_USE_CMPXCHG_LOCKREF if 64BIT 71 select ARCH_USE_MEMTEST 72 select ARCH_USE_QUEUED_RWLOCKS 73 select ARCH_USES_CFI_TRAPS if CFI_CLANG 74 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU 75 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 76 select ARCH_WANT_FRAME_POINTERS 77 select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT 78 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 79 select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL 80 select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP 81 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 82 select ARCH_WANTS_NO_INSTR 83 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 84 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU 85 select BUILDTIME_TABLE_SORT if MMU 86 select CLINT_TIMER if RISCV_M_MODE 87 select CLONE_BACKWARDS 88 select COMMON_CLK 89 select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND 90 select EDAC_SUPPORT 91 select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE) 92 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE 93 select GENERIC_ARCH_TOPOLOGY 94 select GENERIC_ATOMIC64 if !64BIT 95 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 96 select GENERIC_CPU_DEVICES 97 select GENERIC_EARLY_IOREMAP 98 select GENERIC_ENTRY 99 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 100 select GENERIC_IDLE_POLL_SETUP 101 select GENERIC_IOREMAP if MMU 102 select GENERIC_IRQ_IPI if SMP 103 select GENERIC_IRQ_IPI_MUX if SMP 104 select GENERIC_IRQ_MULTI_HANDLER 105 select GENERIC_IRQ_SHOW 106 select GENERIC_IRQ_SHOW_LEVEL 107 select GENERIC_LIB_DEVMEM_IS_ALLOWED 108 select GENERIC_PCI_IOMAP 109 select GENERIC_PTDUMP if MMU 110 select GENERIC_SCHED_CLOCK 111 select GENERIC_SMP_IDLE_THREAD 112 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 113 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO 114 select HARDIRQS_SW_RESEND 115 select HAS_IOPORT if MMU 116 select HAVE_ARCH_AUDITSYSCALL 117 select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP 118 select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT 119 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL 120 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL 121 select HAVE_ARCH_KASAN if MMU && 64BIT 122 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT 123 select HAVE_ARCH_KFENCE if MMU && 64BIT 124 select HAVE_ARCH_KGDB if !XIP_KERNEL 125 select HAVE_ARCH_KGDB_QXFER_PKT 126 select HAVE_ARCH_MMAP_RND_BITS if MMU 127 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 128 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 129 select HAVE_ARCH_SECCOMP_FILTER 130 select HAVE_ARCH_STACKLEAK 131 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 132 select HAVE_ARCH_TRACEHOOK 133 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU 134 select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD 135 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT 136 select HAVE_ASM_MODVERSIONS 137 select HAVE_CONTEXT_TRACKING_USER 138 select HAVE_DEBUG_KMEMLEAK 139 select HAVE_DMA_CONTIGUOUS if MMU 140 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) 141 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 142 select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE 143 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 144 select HAVE_FUNCTION_GRAPH_TRACER 145 select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER 146 select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION 147 select HAVE_EBPF_JIT if MMU 148 select HAVE_GUP_FAST if MMU 149 select HAVE_FUNCTION_ARG_ACCESS_API 150 select HAVE_FUNCTION_ERROR_INJECTION 151 select HAVE_GCC_PLUGINS 152 select HAVE_GENERIC_VDSO if MMU && 64BIT 153 select HAVE_IRQ_TIME_ACCOUNTING 154 select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT 155 select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT 156 select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT 157 select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT 158 select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT 159 select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT 160 select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT 161 select HAVE_KPROBES if !XIP_KERNEL 162 select HAVE_KRETPROBES if !XIP_KERNEL 163 # https://github.com/ClangBuiltLinux/linux/issues/1881 164 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD 165 select HAVE_MOVE_PMD 166 select HAVE_MOVE_PUD 167 select HAVE_PAGE_SIZE_4KB 168 select HAVE_PCI 169 select HAVE_PERF_EVENTS 170 select HAVE_PERF_REGS 171 select HAVE_PERF_USER_STACK_DUMP 172 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 173 select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL 174 select HAVE_REGS_AND_STACK_ACCESS_API 175 select HAVE_RETHOOK if !XIP_KERNEL 176 select HAVE_RSEQ 177 select HAVE_RUST if 64BIT 178 select HAVE_SAMPLE_FTRACE_DIRECT 179 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 180 select HAVE_STACKPROTECTOR 181 select HAVE_SYSCALL_TRACEPOINTS 182 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU 183 select IRQ_DOMAIN 184 select IRQ_FORCED_THREADING 185 select KASAN_VMALLOC if KASAN 186 select LOCK_MM_AND_FIND_VMA 187 select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU 188 select MODULES_USE_ELF_RELA if MODULES 189 select OF 190 select OF_EARLY_FLATTREE 191 select OF_IRQ 192 select PCI_DOMAINS_GENERIC if PCI 193 select PCI_ECAM if (ACPI && PCI) 194 select PCI_MSI if PCI 195 select RISCV_ALTERNATIVE if !XIP_KERNEL 196 select RISCV_APLIC 197 select RISCV_IMSIC 198 select RISCV_INTC 199 select RISCV_TIMER if RISCV_SBI 200 select SIFIVE_PLIC 201 select SPARSE_IRQ 202 select SYSCTL_EXCEPTION_TRACE 203 select THREAD_INFO_IN_TASK 204 select TRACE_IRQFLAGS_SUPPORT 205 select UACCESS_MEMCPY if !MMU 206 select ZONE_DMA32 if 64BIT 207 208config CLANG_SUPPORTS_DYNAMIC_FTRACE 209 def_bool CC_IS_CLANG 210 # https://github.com/ClangBuiltLinux/linux/issues/1817 211 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 212 213config GCC_SUPPORTS_DYNAMIC_FTRACE 214 def_bool CC_IS_GCC 215 depends on $(cc-option,-fpatchable-function-entry=8) 216 217config HAVE_SHADOW_CALL_STACK 218 def_bool $(cc-option,-fsanitize=shadow-call-stack) 219 # https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769 220 depends on $(ld-option,--no-relax-gp) 221 222config RISCV_USE_LINKER_RELAXATION 223 def_bool y 224 # https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985 225 depends on !LD_IS_LLD || LLD_VERSION >= 150000 226 227# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6 228config ARCH_HAS_BROKEN_DWARF5 229 def_bool y 230 depends on RISCV_USE_LINKER_RELAXATION 231 # https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a 232 depends on AS_IS_LLVM && AS_VERSION < 180000 233 # https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77 234 depends on LD_IS_LLD && LLD_VERSION < 180000 235 236config ARCH_MMAP_RND_BITS_MIN 237 default 18 if 64BIT 238 default 8 239 240config ARCH_MMAP_RND_COMPAT_BITS_MIN 241 default 8 242 243# max bits determined by the following formula: 244# VA_BITS - PAGE_SHIFT - 3 245config ARCH_MMAP_RND_BITS_MAX 246 default 24 if 64BIT # SV39 based 247 default 17 248 249config ARCH_MMAP_RND_COMPAT_BITS_MAX 250 default 17 251 252# set if we run in machine mode, cleared if we run in supervisor mode 253config RISCV_M_MODE 254 bool "Build a kernel that runs in machine mode" 255 depends on !MMU 256 default y 257 help 258 Select this option if you want to run the kernel in M-mode, 259 without the assistance of any other firmware. 260 261# set if we are running in S-mode and can use SBI calls 262config RISCV_SBI 263 bool 264 depends on !RISCV_M_MODE 265 default y 266 267config MMU 268 bool "MMU-based Paged Memory Management Support" 269 default y 270 help 271 Select if you want MMU-based virtualised addressing space 272 support by paged memory management. If unsure, say 'Y'. 273 274config PAGE_OFFSET 275 hex 276 default 0x80000000 if !MMU && RISCV_M_MODE 277 default 0x80200000 if !MMU 278 default 0xc0000000 if 32BIT 279 default 0xff60000000000000 if 64BIT 280 281config KASAN_SHADOW_OFFSET 282 hex 283 depends on KASAN_GENERIC 284 default 0xdfffffff00000000 if 64BIT 285 default 0xffffffff if 32BIT 286 287config ARCH_FLATMEM_ENABLE 288 def_bool !NUMA 289 290config ARCH_SPARSEMEM_ENABLE 291 def_bool y 292 depends on MMU 293 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM 294 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT 295 296config ARCH_SELECT_MEMORY_MODEL 297 def_bool ARCH_SPARSEMEM_ENABLE 298 299config ARCH_SUPPORTS_UPROBES 300 def_bool y 301 302config STACKTRACE_SUPPORT 303 def_bool y 304 305config GENERIC_BUG 306 def_bool y 307 depends on BUG 308 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 309 310config GENERIC_BUG_RELATIVE_POINTERS 311 bool 312 313config GENERIC_CALIBRATE_DELAY 314 def_bool y 315 316config GENERIC_CSUM 317 def_bool y 318 319config GENERIC_HWEIGHT 320 def_bool y 321 322config FIX_EARLYCON_MEM 323 def_bool MMU 324 325config PGTABLE_LEVELS 326 int 327 default 5 if 64BIT 328 default 2 329 330config LOCKDEP_SUPPORT 331 def_bool y 332 333config RISCV_DMA_NONCOHERENT 334 bool 335 select ARCH_HAS_DMA_PREP_COHERENT 336 select ARCH_HAS_SETUP_DMA_OPS 337 select ARCH_HAS_SYNC_DMA_FOR_CPU 338 select ARCH_HAS_SYNC_DMA_FOR_DEVICE 339 select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB 340 341config RISCV_NONSTANDARD_CACHE_OPS 342 bool 343 help 344 This enables function pointer support for non-standard noncoherent 345 systems to handle cache management. 346 347config AS_HAS_INSN 348 def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) 349 350config AS_HAS_OPTION_ARCH 351 # https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4 352 def_bool y 353 depends on $(as-instr, .option arch$(comma) +m) 354 355source "arch/riscv/Kconfig.socs" 356source "arch/riscv/Kconfig.errata" 357 358menu "Platform type" 359 360config NONPORTABLE 361 bool "Allow configurations that result in non-portable kernels" 362 help 363 RISC-V kernel binaries are compatible between all known systems 364 whenever possible, but there are some use cases that can only be 365 satisfied by configurations that result in kernel binaries that are 366 not portable between systems. 367 368 Selecting N does not guarantee kernels will be portable to all known 369 systems. Selecting any of the options guarded by NONPORTABLE will 370 result in kernel binaries that are unlikely to be portable between 371 systems. 372 373 If unsure, say N. 374 375choice 376 prompt "Base ISA" 377 default ARCH_RV64I 378 help 379 This selects the base ISA that this kernel will target and must match 380 the target platform. 381 382config ARCH_RV32I 383 bool "RV32I" 384 depends on NONPORTABLE 385 select 32BIT 386 select GENERIC_LIB_ASHLDI3 387 select GENERIC_LIB_ASHRDI3 388 select GENERIC_LIB_LSHRDI3 389 select GENERIC_LIB_UCMPDI2 390 391config ARCH_RV64I 392 bool "RV64I" 393 select 64BIT 394 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 395 select SWIOTLB if MMU 396 397endchoice 398 399# We must be able to map all physical memory into the kernel, but the compiler 400# is still a bit more efficient when generating code if it's setup in a manner 401# such that it can only map 2GiB of memory. 402choice 403 prompt "Kernel Code Model" 404 default CMODEL_MEDLOW if 32BIT 405 default CMODEL_MEDANY if 64BIT 406 407 config CMODEL_MEDLOW 408 bool "medium low code model" 409 config CMODEL_MEDANY 410 bool "medium any code model" 411endchoice 412 413config MODULE_SECTIONS 414 bool 415 select HAVE_MOD_ARCH_SPECIFIC 416 417config SMP 418 bool "Symmetric Multi-Processing" 419 help 420 This enables support for systems with more than one CPU. If 421 you say N here, the kernel will run on single and 422 multiprocessor machines, but will use only one CPU of a 423 multiprocessor machine. If you say Y here, the kernel will run 424 on many, but not all, single processor machines. On a single 425 processor machine, the kernel will run faster if you say N 426 here. 427 428 If you don't know what to do here, say N. 429 430config SCHED_MC 431 bool "Multi-core scheduler support" 432 depends on SMP 433 help 434 Multi-core scheduler support improves the CPU scheduler's decision 435 making when dealing with multi-core CPU chips at a cost of slightly 436 increased overhead in some places. If unsure say N here. 437 438config NR_CPUS 439 int "Maximum number of CPUs (2-512)" 440 depends on SMP 441 range 2 512 if !RISCV_SBI_V01 442 range 2 32 if RISCV_SBI_V01 && 32BIT 443 range 2 64 if RISCV_SBI_V01 && 64BIT 444 default "32" if 32BIT 445 default "64" if 64BIT 446 447config HOTPLUG_CPU 448 bool "Support for hot-pluggable CPUs" 449 depends on SMP 450 select GENERIC_IRQ_MIGRATION 451 help 452 453 Say Y here to experiment with turning CPUs off and on. CPUs 454 can be controlled through /sys/devices/system/cpu. 455 456 Say N if you want to disable CPU hotplug. 457 458choice 459 prompt "CPU Tuning" 460 default TUNE_GENERIC 461 462config TUNE_GENERIC 463 bool "generic" 464 465endchoice 466 467# Common NUMA Features 468config NUMA 469 bool "NUMA Memory Allocation and Scheduler Support" 470 depends on SMP && MMU 471 select ARCH_SUPPORTS_NUMA_BALANCING 472 select GENERIC_ARCH_NUMA 473 select HAVE_SETUP_PER_CPU_AREA 474 select NEED_PER_CPU_EMBED_FIRST_CHUNK 475 select NEED_PER_CPU_PAGE_FIRST_CHUNK 476 select OF_NUMA 477 select USE_PERCPU_NUMA_NODE_ID 478 help 479 Enable NUMA (Non-Uniform Memory Access) support. 480 481 The kernel will try to allocate memory used by a CPU on the 482 local memory of the CPU and add some more NUMA awareness to the kernel. 483 484config NODES_SHIFT 485 int "Maximum NUMA Nodes (as a power of 2)" 486 range 1 10 487 default "2" 488 depends on NUMA 489 help 490 Specify the maximum number of NUMA Nodes available on the target 491 system. Increases memory reserved to accommodate various tables. 492 493config RISCV_ALTERNATIVE 494 bool 495 depends on !XIP_KERNEL 496 help 497 This Kconfig allows the kernel to automatically patch the 498 erratum or cpufeature required by the execution platform at run 499 time. The code patching overhead is minimal, as it's only done 500 once at boot and once on each module load. 501 502config RISCV_ALTERNATIVE_EARLY 503 bool 504 depends on RISCV_ALTERNATIVE 505 help 506 Allows early patching of the kernel for special errata 507 508config RISCV_ISA_C 509 bool "Emit compressed instructions when building Linux" 510 default y 511 help 512 Adds "C" to the ISA subsets that the toolchain is allowed to emit 513 when building Linux, which results in compressed instructions in the 514 Linux binary. 515 516 If you don't know what to do here, say Y. 517 518config RISCV_ISA_SVNAPOT 519 bool "Svnapot extension support for supervisor mode NAPOT pages" 520 depends on 64BIT && MMU 521 depends on RISCV_ALTERNATIVE 522 default y 523 help 524 Allow kernel to detect the Svnapot ISA-extension dynamically at boot 525 time and enable its usage. 526 527 The Svnapot extension is used to mark contiguous PTEs as a range 528 of contiguous virtual-to-physical translations for a naturally 529 aligned power-of-2 (NAPOT) granularity larger than the base 4KB page 530 size. When HUGETLBFS is also selected this option unconditionally 531 allocates some memory for each NAPOT page size supported by the kernel. 532 When optimizing for low memory consumption and for platforms without 533 the Svnapot extension, it may be better to say N here. 534 535 If you don't know what to do here, say Y. 536 537config RISCV_ISA_SVPBMT 538 bool "Svpbmt extension support for supervisor mode page-based memory types" 539 depends on 64BIT && MMU 540 depends on RISCV_ALTERNATIVE 541 default y 542 help 543 Adds support to dynamically detect the presence of the Svpbmt 544 ISA-extension (Supervisor-mode: page-based memory types) and 545 enable its usage. 546 547 The memory type for a page contains a combination of attributes 548 that indicate the cacheability, idempotency, and ordering 549 properties for access to that page. 550 551 The Svpbmt extension is only available on 64-bit cpus. 552 553 If you don't know what to do here, say Y. 554 555config TOOLCHAIN_HAS_V 556 bool 557 default y 558 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv) 559 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv) 560 depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 561 depends on AS_HAS_OPTION_ARCH 562 563config RISCV_ISA_V 564 bool "VECTOR extension support" 565 depends on TOOLCHAIN_HAS_V 566 depends on FPU 567 select DYNAMIC_SIGFRAME 568 default y 569 help 570 Say N here if you want to disable all vector related procedure 571 in the kernel. 572 573 If you don't know what to do here, say Y. 574 575config RISCV_ISA_V_DEFAULT_ENABLE 576 bool "Enable userspace Vector by default" 577 depends on RISCV_ISA_V 578 default y 579 help 580 Say Y here if you want to enable Vector in userspace by default. 581 Otherwise, userspace has to make explicit prctl() call to enable 582 Vector, or enable it via the sysctl interface. 583 584 If you don't know what to do here, say Y. 585 586config RISCV_ISA_V_UCOPY_THRESHOLD 587 int "Threshold size for vectorized user copies" 588 depends on RISCV_ISA_V 589 default 768 590 help 591 Prefer using vectorized copy_to_user()/copy_from_user() when the 592 workload size exceeds this value. 593 594config RISCV_ISA_V_PREEMPTIVE 595 bool "Run kernel-mode Vector with kernel preemption" 596 depends on PREEMPTION 597 depends on RISCV_ISA_V 598 default y 599 help 600 Usually, in-kernel SIMD routines are run with preemption disabled. 601 Functions which envoke long running SIMD thus must yield core's 602 vector unit to prevent blocking other tasks for too long. 603 604 This config allows kernel to run SIMD without explicitly disable 605 preemption. Enabling this config will result in higher memory 606 consumption due to the allocation of per-task's kernel Vector context. 607 608config RISCV_ISA_ZAWRS 609 bool "Zawrs extension support for more efficient busy waiting" 610 depends on RISCV_ALTERNATIVE 611 default y 612 help 613 The Zawrs extension defines instructions to be used in polling loops 614 which allow a hart to enter a low-power state or to trap to the 615 hypervisor while waiting on a store to a memory location. Enable the 616 use of these instructions in the kernel when the Zawrs extension is 617 detected at boot. 618 619 If you don't know what to do here, say Y. 620 621config TOOLCHAIN_HAS_ZBB 622 bool 623 default y 624 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) 625 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) 626 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 627 depends on AS_HAS_OPTION_ARCH 628 629# This symbol indicates that the toolchain supports all v1.0 vector crypto 630# extensions, including Zvk*, Zvbb, and Zvbc. LLVM added all of these at once. 631# binutils added all except Zvkb, then added Zvkb. So we just check for Zvkb. 632config TOOLCHAIN_HAS_VECTOR_CRYPTO 633 def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb) 634 depends on AS_HAS_OPTION_ARCH 635 636config RISCV_ISA_ZBA 637 bool "Zba extension support for bit manipulation instructions" 638 default y 639 help 640 Add support for enabling optimisations in the kernel when the Zba 641 extension is detected at boot. 642 643 The Zba extension provides instructions to accelerate the generation 644 of addresses that index into arrays of basic data types. 645 646 If you don't know what to do here, say Y. 647 648config RISCV_ISA_ZBB 649 bool "Zbb extension support for bit manipulation instructions" 650 depends on TOOLCHAIN_HAS_ZBB 651 depends on RISCV_ALTERNATIVE 652 default y 653 help 654 Adds support to dynamically detect the presence of the ZBB 655 extension (basic bit manipulation) and enable its usage. 656 657 The Zbb extension provides instructions to accelerate a number 658 of bit-specific operations (count bit population, sign extending, 659 bitrotation, etc). 660 661 If you don't know what to do here, say Y. 662 663config TOOLCHAIN_HAS_ZBC 664 bool 665 default y 666 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc) 667 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc) 668 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 669 depends on AS_HAS_OPTION_ARCH 670 671config RISCV_ISA_ZBC 672 bool "Zbc extension support for carry-less multiplication instructions" 673 depends on TOOLCHAIN_HAS_ZBC 674 depends on MMU 675 depends on RISCV_ALTERNATIVE 676 default y 677 help 678 Adds support to dynamically detect the presence of the Zbc 679 extension (carry-less multiplication) and enable its usage. 680 681 The Zbc extension could accelerate CRC (cyclic redundancy check) 682 calculations. 683 684 If you don't know what to do here, say Y. 685 686config RISCV_ISA_ZICBOM 687 bool "Zicbom extension support for non-coherent DMA operation" 688 depends on MMU 689 depends on RISCV_ALTERNATIVE 690 default y 691 select RISCV_DMA_NONCOHERENT 692 select DMA_DIRECT_REMAP 693 help 694 Adds support to dynamically detect the presence of the ZICBOM 695 extension (Cache Block Management Operations) and enable its 696 usage. 697 698 The Zicbom extension can be used to handle for example 699 non-coherent DMA support on devices that need it. 700 701 If you don't know what to do here, say Y. 702 703config RISCV_ISA_ZICBOZ 704 bool "Zicboz extension support for faster zeroing of memory" 705 depends on RISCV_ALTERNATIVE 706 default y 707 help 708 Enable the use of the Zicboz extension (cbo.zero instruction) 709 when available. 710 711 The Zicboz extension is used for faster zeroing of memory. 712 713 If you don't know what to do here, say Y. 714 715config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 716 def_bool y 717 # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc 718 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd 719 depends on AS_IS_GNU && AS_VERSION >= 23600 720 help 721 Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer 722 20191213 version, which moves some instructions from the I extension to 723 the Zicsr and Zifencei extensions. This requires explicitly specifying 724 Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr 725 and Zifencei are supported in binutils from version 2.36 onwards. 726 To make life easier, and avoid forcing toolchains that default to a 727 newer ISA spec to version 2.2, relax the check to binutils >= 2.36. 728 For clang < 17 or GCC < 11.3.0, for which this is not possible or need 729 special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC. 730 731config TOOLCHAIN_NEEDS_OLD_ISA_SPEC 732 def_bool y 733 depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 734 # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16 735 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671 736 depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300) 737 help 738 Certain versions of clang and GCC do not support zicsr and zifencei via 739 -march. This option causes an older ISA spec compatible with these older 740 versions of clang and GCC to be passed to GAS, which has the same result 741 as passing zicsr and zifencei to -march. 742 743config FPU 744 bool "FPU support" 745 default y 746 help 747 Say N here if you want to disable all floating-point related procedure 748 in the kernel. 749 750 If you don't know what to do here, say Y. 751 752config IRQ_STACKS 753 bool "Independent irq & softirq stacks" if EXPERT 754 default y 755 select HAVE_IRQ_EXIT_ON_IRQ_STACK 756 select HAVE_SOFTIRQ_ON_OWN_STACK 757 help 758 Add independent irq & softirq stacks for percpu to prevent kernel stack 759 overflows. We may save some memory footprint by disabling IRQ_STACKS. 760 761config THREAD_SIZE_ORDER 762 int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT 763 range 0 4 764 default 1 if 32BIT && !KASAN 765 default 3 if 64BIT && KASAN 766 default 2 767 help 768 Specify the Pages of thread stack size (from 4KB to 64KB), which also 769 affects irq stack size, which is equal to thread stack size. 770 771config RISCV_MISALIGNED 772 bool 773 select SYSCTL_ARCH_UNALIGN_ALLOW 774 help 775 Embed support for emulating misaligned loads and stores. 776 777choice 778 prompt "Unaligned Accesses Support" 779 default RISCV_PROBE_UNALIGNED_ACCESS 780 help 781 This determines the level of support for unaligned accesses. This 782 information is used by the kernel to perform optimizations. It is also 783 exposed to user space via the hwprobe syscall. The hardware will be 784 probed at boot by default. 785 786config RISCV_PROBE_UNALIGNED_ACCESS 787 bool "Probe for hardware unaligned access support" 788 select RISCV_MISALIGNED 789 help 790 During boot, the kernel will run a series of tests to determine the 791 speed of unaligned accesses. This probing will dynamically determine 792 the speed of unaligned accesses on the underlying system. If unaligned 793 memory accesses trap into the kernel as they are not supported by the 794 system, the kernel will emulate the unaligned accesses to preserve the 795 UABI. 796 797config RISCV_EMULATED_UNALIGNED_ACCESS 798 bool "Emulate unaligned access where system support is missing" 799 select RISCV_MISALIGNED 800 help 801 If unaligned memory accesses trap into the kernel as they are not 802 supported by the system, the kernel will emulate the unaligned 803 accesses to preserve the UABI. When the underlying system does support 804 unaligned accesses, the unaligned accesses are assumed to be slow. 805 806config RISCV_SLOW_UNALIGNED_ACCESS 807 bool "Assume the system supports slow unaligned memory accesses" 808 depends on NONPORTABLE 809 help 810 Assume that the system supports slow unaligned memory accesses. The 811 kernel and userspace programs may not be able to run at all on systems 812 that do not support unaligned memory accesses. 813 814config RISCV_EFFICIENT_UNALIGNED_ACCESS 815 bool "Assume the system supports fast unaligned memory accesses" 816 depends on NONPORTABLE 817 select DCACHE_WORD_ACCESS if MMU 818 select HAVE_EFFICIENT_UNALIGNED_ACCESS 819 help 820 Assume that the system supports fast unaligned memory accesses. When 821 enabled, this option improves the performance of the kernel on such 822 systems. However, the kernel and userspace programs will run much more 823 slowly, or will not be able to run at all, on systems that do not 824 support efficient unaligned memory accesses. 825 826endchoice 827 828source "arch/riscv/Kconfig.vendor" 829 830endmenu # "Platform type" 831 832menu "Kernel features" 833 834source "kernel/Kconfig.hz" 835 836config RISCV_SBI_V01 837 bool "SBI v0.1 support" 838 depends on RISCV_SBI 839 help 840 This config allows kernel to use SBI v0.1 APIs. This will be 841 deprecated in future once legacy M-mode software are no longer in use. 842 843config RISCV_BOOT_SPINWAIT 844 bool "Spinwait booting method" 845 depends on SMP 846 default y if RISCV_SBI_V01 || RISCV_M_MODE 847 help 848 This enables support for booting Linux via spinwait method. In the 849 spinwait method, all cores randomly jump to Linux. One of the cores 850 gets chosen via lottery and all other keep spinning on a percpu 851 variable. This method cannot support CPU hotplug and sparse hartid 852 scheme. It should be only enabled for M-mode Linux or platforms relying 853 on older firmware without SBI HSM extension. All other platforms should 854 rely on ordered booting via SBI HSM extension which gets chosen 855 dynamically at runtime if the firmware supports it. 856 857 Since spinwait is incompatible with sparse hart IDs, it requires 858 NR_CPUS be large enough to contain the physical hart ID of the first 859 hart to enter Linux. 860 861 If unsure what to do here, say N. 862 863config ARCH_SUPPORTS_KEXEC 864 def_bool y 865 866config ARCH_SELECTS_KEXEC 867 def_bool y 868 depends on KEXEC 869 select HOTPLUG_CPU if SMP 870 871config ARCH_SUPPORTS_KEXEC_FILE 872 def_bool 64BIT 873 874config ARCH_SELECTS_KEXEC_FILE 875 def_bool y 876 depends on KEXEC_FILE 877 select HAVE_IMA_KEXEC if IMA 878 select KEXEC_ELF 879 880config ARCH_SUPPORTS_KEXEC_PURGATORY 881 def_bool ARCH_SUPPORTS_KEXEC_FILE 882 883config ARCH_SUPPORTS_CRASH_DUMP 884 def_bool y 885 886config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 887 def_bool CRASH_RESERVE 888 889config COMPAT 890 bool "Kernel support for 32-bit U-mode" 891 default 64BIT 892 depends on 64BIT && MMU 893 help 894 This option enables support for a 32-bit U-mode running under a 64-bit 895 kernel at S-mode. riscv32-specific components such as system calls, 896 the user helper functions (vdso), signal rt_frame functions and the 897 ptrace interface are handled appropriately by the kernel. 898 899 If you want to execute 32-bit userspace applications, say Y. 900 901config PARAVIRT 902 bool "Enable paravirtualization code" 903 depends on RISCV_SBI 904 help 905 This changes the kernel so it can modify itself when it is run 906 under a hypervisor, potentially improving performance significantly 907 over full virtualization. 908 909config PARAVIRT_TIME_ACCOUNTING 910 bool "Paravirtual steal time accounting" 911 depends on PARAVIRT 912 help 913 Select this option to enable fine granularity task steal time 914 accounting. Time spent executing other tasks in parallel with 915 the current vCPU is discounted from the vCPU power. To account for 916 that, there can be a small performance impact. 917 918 If in doubt, say N here. 919 920config RELOCATABLE 921 bool "Build a relocatable kernel" 922 depends on MMU && 64BIT && !XIP_KERNEL 923 select MODULE_SECTIONS if MODULES 924 help 925 This builds a kernel as a Position Independent Executable (PIE), 926 which retains all relocation metadata required to relocate the 927 kernel binary at runtime to a different virtual address than the 928 address it was linked at. 929 Since RISCV uses the RELA relocation format, this requires a 930 relocation pass at runtime even if the kernel is loaded at the 931 same address it was linked at. 932 933 If unsure, say N. 934 935config RANDOMIZE_BASE 936 bool "Randomize the address of the kernel image" 937 select RELOCATABLE 938 depends on MMU && 64BIT && !XIP_KERNEL 939 help 940 Randomizes the virtual address at which the kernel image is 941 loaded, as a security feature that deters exploit attempts 942 relying on knowledge of the location of kernel internals. 943 944 It is the bootloader's job to provide entropy, by passing a 945 random u64 value in /chosen/kaslr-seed at kernel entry. 946 947 When booting via the UEFI stub, it will invoke the firmware's 948 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 949 to the kernel proper. In addition, it will randomise the physical 950 location of the kernel Image as well. 951 952 If unsure, say N. 953 954endmenu # "Kernel features" 955 956menu "Boot options" 957 958config CMDLINE 959 string "Built-in kernel command line" 960 help 961 For most platforms, the arguments for the kernel's command line 962 are provided at run-time, during boot. However, there are cases 963 where either no arguments are being provided or the provided 964 arguments are insufficient or even invalid. 965 966 When that occurs, it is possible to define a built-in command 967 line here and choose how the kernel should use it later on. 968 969choice 970 prompt "Built-in command line usage" 971 depends on CMDLINE != "" 972 default CMDLINE_FALLBACK 973 help 974 Choose how the kernel will handle the provided built-in command 975 line. 976 977config CMDLINE_FALLBACK 978 bool "Use bootloader kernel arguments if available" 979 help 980 Use the built-in command line as fallback in case we get nothing 981 during boot. This is the default behaviour. 982 983config CMDLINE_EXTEND 984 bool "Extend bootloader kernel arguments" 985 help 986 The command-line arguments provided during boot will be 987 appended to the built-in command line. This is useful in 988 cases where the provided arguments are insufficient and 989 you don't want to or cannot modify them. 990 991config CMDLINE_FORCE 992 bool "Always use the default kernel command string" 993 help 994 Always use the built-in command line, even if we get one during 995 boot. This is useful in case you need to override the provided 996 command line on systems where you don't have or want control 997 over it. 998 999endchoice 1000 1001config EFI_STUB 1002 bool 1003 1004config EFI 1005 bool "UEFI runtime support" 1006 depends on OF && !XIP_KERNEL 1007 depends on MMU 1008 default y 1009 select ARCH_SUPPORTS_ACPI if 64BIT 1010 select EFI_GENERIC_STUB 1011 select EFI_PARAMS_FROM_FDT 1012 select EFI_RUNTIME_WRAPPERS 1013 select EFI_STUB 1014 select LIBFDT 1015 select RISCV_ISA_C 1016 select UCS2_STRING 1017 help 1018 This option provides support for runtime services provided 1019 by UEFI firmware (such as non-volatile variables, realtime 1020 clock, and platform reset). A UEFI stub is also provided to 1021 allow the kernel to be booted as an EFI application. This 1022 is only useful on systems that have UEFI firmware. 1023 1024config DMI 1025 bool "Enable support for SMBIOS (DMI) tables" 1026 depends on EFI 1027 default y 1028 help 1029 This enables SMBIOS/DMI feature for systems. 1030 1031 This option is only useful on systems that have UEFI firmware. 1032 However, even with this option, the resultant kernel should 1033 continue to boot on existing non-UEFI platforms. 1034 1035config CC_HAVE_STACKPROTECTOR_TLS 1036 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 1037 1038config STACKPROTECTOR_PER_TASK 1039 def_bool y 1040 depends on !RANDSTRUCT 1041 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 1042 1043config PHYS_RAM_BASE_FIXED 1044 bool "Explicitly specified physical RAM address" 1045 depends on NONPORTABLE 1046 default n 1047 1048config PHYS_RAM_BASE 1049 hex "Platform Physical RAM address" 1050 depends on PHYS_RAM_BASE_FIXED 1051 default "0x80000000" 1052 help 1053 This is the physical address of RAM in the system. It has to be 1054 explicitly specified to run early relocations of read-write data 1055 from flash to RAM. 1056 1057config XIP_KERNEL 1058 bool "Kernel Execute-In-Place from ROM" 1059 depends on MMU && SPARSEMEM && NONPORTABLE 1060 # This prevents XIP from being enabled by all{yes,mod}config, which 1061 # fail to build since XIP doesn't support large kernels. 1062 depends on !COMPILE_TEST 1063 select PHYS_RAM_BASE_FIXED 1064 help 1065 Execute-In-Place allows the kernel to run from non-volatile storage 1066 directly addressable by the CPU, such as NOR flash. This saves RAM 1067 space since the text section of the kernel is not loaded from flash 1068 to RAM. Read-write sections, such as the data section and stack, 1069 are still copied to RAM. The XIP kernel is not compressed since 1070 it has to run directly from flash, so it will take more space to 1071 store it. The flash address used to link the kernel object files, 1072 and for storing it, is configuration dependent. Therefore, if you 1073 say Y here, you must know the proper physical address where to 1074 store the kernel image depending on your own flash memory usage. 1075 1076 Also note that the make target becomes "make xipImage" rather than 1077 "make zImage" or "make Image". The final kernel binary to put in 1078 ROM memory will be arch/riscv/boot/xipImage. 1079 1080 SPARSEMEM is required because the kernel text and rodata that are 1081 flash resident are not backed by memmap, then any attempt to get 1082 a struct page on those regions will trigger a fault. 1083 1084 If unsure, say N. 1085 1086config XIP_PHYS_ADDR 1087 hex "XIP Kernel Physical Location" 1088 depends on XIP_KERNEL 1089 default "0x21000000" 1090 help 1091 This is the physical address in your flash memory the kernel will 1092 be linked for and stored to. This address is dependent on your 1093 own flash usage. 1094 1095config RISCV_ISA_FALLBACK 1096 bool "Permit falling back to parsing riscv,isa for extension support by default" 1097 default y 1098 help 1099 Parsing the "riscv,isa" devicetree property has been deprecated and 1100 replaced by a list of explicitly defined strings. For compatibility 1101 with existing platforms, the kernel will fall back to parsing the 1102 "riscv,isa" property if the replacements are not found. 1103 1104 Selecting N here will result in a kernel that does not use the 1105 fallback, unless the commandline "riscv_isa_fallback" parameter is 1106 present. 1107 1108 Please see the dt-binding, located at 1109 Documentation/devicetree/bindings/riscv/extensions.yaml for details 1110 on the replacement properties, "riscv,isa-base" and 1111 "riscv,isa-extensions". 1112 1113config BUILTIN_DTB 1114 bool "Built-in device tree" 1115 depends on OF && NONPORTABLE 1116 help 1117 Build a device tree into the Linux image. 1118 This option should be selected if no bootloader is being used. 1119 If unsure, say N. 1120 1121 1122config BUILTIN_DTB_SOURCE 1123 string "Built-in device tree source" 1124 depends on BUILTIN_DTB 1125 help 1126 DTS file path (without suffix, relative to arch/riscv/boot/dts) 1127 for the DTS file that will be used to produce the DTB linked into the 1128 kernel. 1129 1130endmenu # "Boot options" 1131 1132config PORTABLE 1133 bool 1134 default !NONPORTABLE 1135 select EFI 1136 select MMU 1137 select OF 1138 1139config ARCH_PROC_KCORE_TEXT 1140 def_bool y 1141 1142menu "Power management options" 1143 1144source "kernel/power/Kconfig" 1145 1146config ARCH_HIBERNATION_POSSIBLE 1147 def_bool y 1148 1149config ARCH_HIBERNATION_HEADER 1150 def_bool HIBERNATION 1151 1152config ARCH_SUSPEND_POSSIBLE 1153 def_bool y 1154 1155endmenu # "Power management options" 1156 1157menu "CPU Power Management" 1158 1159source "drivers/cpuidle/Kconfig" 1160 1161source "drivers/cpufreq/Kconfig" 1162 1163endmenu # "CPU Power Management" 1164 1165source "arch/riscv/kvm/Kconfig" 1166 1167source "drivers/acpi/Kconfig" 1168